Aim: To determine prognosic significance of RAS oncogene mutation detection in patients with metastatic colorectal carcinoma (mCRC). Introduction: CRC is still third most common cancer of both genders and second cause of death from malignancy in Western countries. In recent years, detecting RAS mutation in mCRC tumor tissue has became an imperative in selecting patients for monoclonal antibodies targeted therapy to Epidermal Growth Factor Receptor (EGFR). Nevertheless, there is no consensus regarding prognostic relevance of determining RAS status in patients with mCRC. Material and methods: Study included 116 patients with surgicaly resected CRC at Oncology Insitute of Vojvodina between January and December 2016. KRAS mutation detection was performed in formalin-fixed paraffin embeded tumor tissue samples processed by real-time chain polymerase reaction (real-time PCR) and applyng Cobas® KRAS Mutation Test and Cobas® 4800 System for detection of mutations in codons 12/13 and 61 of KRAS gene. Results: Average age in tested population was 65 years, with a male gender predominance (66.4%). Presence of KRAS mutation was found in 50.9% patients: 44.8% in codons 12/13, 4.3% in codon 61 and 1.7% in both codons 12/13 and 61. RAS mutated colorectal carcinomas (n=59) compared with RAS wildtype colorectal cancers, were significantly associated with male gender, moderately differentiated tumors, lymphovascular invasion and local nodal metastases. Conclusion: Our results show that, beside predictive, KRAS can also have prognostic significance regarding risk assesment for lymphovascular invasion and presence of local and distant metastases.

Aim: We present the case of a woman with endobronchial pulmonary synovial sarcoma. Introduction: Primary pulmonary synovial sarcoma is an extremely rare tumor that has the same histomorphological characteristics and chromosomal translocations as the synovial sarcoma of soft tissue origin. Material and Methods: A woman aged 58 years, the smoker, without the current symptoms of the disease, came to our institution because of the nodus that was seen on the CT chest. The polip (26 mm) was located in the lumen of the lower right lobar bronchus. The mediastinal and hilar lymph nodes were not increased. The radiological examination was done as part of a routine control after the meningeoma surgery three years ago. Right lower lobectomy and resection of regional lymph nodes were performed. Results: By a macroscopic examination, in the lumen of the bronchus for the lower right lobes, a clearly limited, nonencapsulated, grayish-white node of 2.6 x 2.6 x 1 cm was found. Histologically, the tumor was showed interweaving fascicular uniform spindle cell with ovoid, pale staining nuclei, and inconspicuous nucleoli, scant cytoplasm and the cell borders indistinct. Immunohistochemical tumor cells were positive for CD99, bcl2 and vimentin. Surgical margins and regional lymph nodes were not affected. A detailed clinical and radiological examination confirmed the primary lung origin of the diagnosed synovial sarcoma. A year after surgery the patient feels good. Conclusion: Morphological and immunohistochemical analysis with detailed clinical and radiological examination confirms the primary lung origin of synovial sarcoma